Today we take electricity for granted and perhaps we do not realize just how useful this discovery has been. Steam was the first invention that replaced wind power. It was used to drive engines and was passed through pipes and radiators to warm rooms. Petrol mixed with air was the next invention that provided power. Exploded in a cylinder, it drove a motor engine. Beyond these simple and direct uses, those forms have not much adaptability.

On the other hand, we make use of electricity in thousands of ways. From the powerful voltages that drive our electric trains to the tiny current needed to work a simple calculator, and from the huge electric magnet in steel works that can lift 10 tons to the tiny electric magnet in a doorbell, all are powered by electricity. An electric current can be made with equal ease to heat a huge mass of molten metal in a furnace, or to boil a jug for a cup of coffee. Other than atomic energy, which has not as yet been harnessed to the full, electricity is the greatest power in the world. It is flexible, and so adaptable for any task for which it is wanted. It travels so easily and with incredible speed along wires or conductors that it can be supplied instantly over vast distances. To generate electricity, huge turbines or generators must be turned. In Australia they use coal or water to drive this machinery. When dams are built, falling water is used to drive the turbines without polluting the atmosphere with smoke from coal. Atomic power is used in several countries but there is always the fear of an accident. A tragedy once occurred at Chernobyl, in Ukraine, at an atomic power plant used to make electricity. The reactor leaked, which caused many deaths through radiation.

Now scientists are examining new ways of creating electricity without harmful effects to the environment. They may harness the tides as they flow in and out of bays. Most importantly, they hope to trap sunlight more efficiently. We do use solar heaters for swimming pools but as yet improvement in the capacity of the solar cells to create more current is necessary. When this happens, electric cars will be viable and the world will rid itself of the toxic gases given off by trucks and cars that burn fossil fuels.

76. The author mentions the sources of energy such as wind, steam, petrol in the first paragraph to ………

A. suggest that electricity should be alternated with safer sources of energy

B. show the usefulness and adaptability of electricity

C. imply that electricity is not the only useful source of energy

D. discuss which source of energy can be a suitable alternative to electricity

77. What does the author mean by saying that electricity is flexible?

A. It is cheap and easy to use. B. It is used to drive motor engines.

C. It can be adapted to various uses. D. It can be made with ease.

78. What do we call machines that make electricity?

A. Voltages B. Electric magnets C. Generators or turbines D. Pipes and radiators

79. The word "they" in the last paragraph refers to ……………..

A. harmful effects B. scientists C. the tides D. new ways

80. The best title for this passage could be …………….

A. "Types of Power Plants” B. “Electricity: Harmful Effects on Our Life”

C. “How to Produce Electricity” D. “Why Electricity Is So Remarkable”

Question

Today we take electricity for granted and perhaps we do not realize just how useful this discovery has been. Steam was the first invention that replaced wind power. It was used to drive engines and was passed through pipes and radiators to warm rooms. Petrol mixed with air was the next invention that provided power. Exploded in a cylinder, it drove a motor engine. Beyond these simple and direct uses, those forms have not much adaptability.

On the other hand, we make use of electricity in thousands of ways. From the powerful voltages that drive our electric trains to the tiny current needed to work a simple calculator, and from the huge electric magnet in steel works that can lift 10 tons to the tiny electric magnet in a doorbell, all are powered by electricity. An electric current can be made with equal ease to heat a huge mass of molten metal in a furnace, or to boil a jug for a cup of coffee. Other than atomic energy, which has not as yet been harnessed to the full, electricity is the greatest power in the world. It is flexible, and so adaptable for any task for which it is wanted. It travels so easily and with incredible speed along wires or conductors that it can be supplied instantly over vast distances. To generate electricity, huge turbines or generators must be turned. In Australia they use coal or water to drive this machinery. When dams are built, falling water is used to drive the turbines without polluting the atmosphere with smoke from coal. Atomic power is used in several countries but there is always the fear of an accident. A tragedy once occurred at Chernobyl, in Ukraine, at an atomic power plant used to make electricity. The reactor leaked, which caused many deaths through radiation.

Now scientists are examining new ways of creating electricity without harmful effects to the environment. They may harness the tides as they flow in and out of bays. Most importantly, they hope to trap sunlight more efficiently. We do use solar heaters for swimming pools but as yet improvement in the capacity of the solar cells to create more current is necessary. When this happens, electric cars will be viable and the world will rid itself of the toxic gases given off by trucks and cars that burn fossil fuels.

76. The author mentions the sources of energy such as wind, steam, petrol in the first paragraph to ………

A. suggest that electricity should be alternated with safer sources of energy

B. show the usefulness and adaptability of electricity

C. imply that electricity is not the only useful source of energy

D. discuss which source of energy can be a suitable alternative to electricity

77. What does the author mean by saying that electricity is flexible?

A. It is cheap and easy to use. B. It is used to drive motor engines.

C. It can be adapted to various uses. D. It can be made with ease.

78. What do we call machines that make electricity?

A. Voltages B. Electric magnets C. Generators or turbines D. Pipes and radiators

79. The word "they" in the last paragraph refers to ……………..

A. harmful effects B. scientists C. the tides D. new ways

80. The best title for this passage could be …………….

A. "Types of Power Plants” B. “Electricity: Harmful Effects on Our Life”

C. “How to Produce Electricity” D. “Why Electricity Is So Remarkable”

Accepted Answer

76. B. show the usefulness and adaptability of electricityB. 77. C. It can be adapted to various uses. 78. C. Generators or turbines 79. C.the tides 80. D. “Why Electricity Is So Remarkable”

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